Build parameters

Every input is a declared build parameter. No resource file reads process.env, so the same parameters produce the same resources, and src/params.ts is the one place any of them is read.

just params="--param postgres=cnpg --param size=large" up
npx chant build src --param target=kubernetes --param ingressClassName=nginx

just up is a chain of targets and just does not thread arguments through dependencies, which is why the params variable exists rather than trailing flags.

Identity and the app

Parameter	Values	Default	Note
env	any string	dev	The app.kubernetes.io/instance label on every resource. Also reads FOUNTAIN_ENV — see below
namespace	any string	fountain
image	an image reference	ghcr.io/binarybourbon/fountain:v0.7.0	Pinned, not a floating tag
host	authority, port allowed	localhost:4000	PUBLIC_URL is scheme://host. Any port is stripped for PHX_HOST, the Ingress rule and certificate SANs
scheme	http · https	http	https turns on fountain’s redirect, HSTS and secure cookies, so whatever terminates TLS must set X-Forwarded-Proto
emailDelivery	none · resend · smtp	none	fountain does not boot without a mail decision; none is a decision with two edges — see below
registrationEnabled	true · false	true	Sets REGISTRATION_ENABLED
firstUserAdmin	true · false	true	Sets FIRST_USER_ADMIN (fountain ADR 0011): the first verified account on an instance with no admin is promoted, audit-recorded. Ignored by images ≤ v0.4.0. false keeps the manual path
databaseSsl	true · false	derived from the postgres seam	false for bundled, true otherwise — see below
otelTraces	none · otlp	none	otlp hands export back to the standard OTEL_EXPORTER_OTLP_* variables, which this repo does not model

The axes

target is where the substrate runs, tier is how durable it is, size is how much of the machine it asks for. Separate questions, and not a free grid: Targets and tiers has which combinations are refused and why.

Parameter	Values	Default	Note
target	k3d · kubernetes	k3d	Picks the seam defaults coherent on that substrate and nothing else. Also reads FOUNTAIN_TARGET
tier	light · ha	light	Replica count, Erlang clustering and backup retention. Also reads FOUNTAIN_TIER
replicas	integer ≥ 1	the tier’s — 1 at light, 2 at ha	Above one replica at light is a build error: the pods must form a cluster or conversation streaming breaks
size	small · medium · large	small at light, large at ha	CPU and memory requests and limits. Changes no shape and refuses no combination

Seams

Seams start from the target’s defaults; setting one replaces exactly that seam and leaves the rest alone. The modes themselves, and the reasoning behind each refusal, are on Seams.

Parameter	Values	k3d	kubernetes	Refuses
postgres	reference · bundled · cnpg	bundled	reference	bundled at tier=ha
secrets	reference · sops · infisical	reference	reference	—
ingress	omit · ingress · traefik	omit	ingress	ingress without ingressClassName
tls	omit · cert-manager	omit	omit	cert-manager with ingress=omit
backups	omit · pg-dump · barman-pitr	pg-dump	omit	barman-pitr without postgres=cnpg; omit with storage=floci
monitoring	omit · prometheus-operator	omit	omit	—
dataPlane	sprites · spritzer	spritzer	sprites	spritzer at tier=ha
storage	s3 · floci	floci	s3	floci at tier=ha; floci with backups=omit

Which of those refusals fire on the default seams of each target is asserted in test/tiers-and-seams.test.ts, so a seam change that shifts the answer fails a build rather than making this table quietly wrong.

monitoring=prometheus-operator, ingress=traefik and secrets=infisical build and a real API server accepts the output, but no controller has reconciled any of them. Status is the authority on what has actually run.

Seam inputs

Parameter	Values	Default	Note
secretName	any string	fountain-secrets	The Secret the app reads its environment from, whatever produced it
pgStorageSize	a quantity	10Gi	The volume for postgres=bundled and postgres=cnpg
pgImage	an image reference	postgres:16	The bundled Postgres, and the client the app’s readiness wait uses
pgStorageClass	any string	unset	Unset means the cluster’s default StorageClass, which is right on k3d. postgres=cnpg
cnpgImage	an image reference	ghcr.io/cloudnative-pg/postgresql:16.4	postgres=cnpg
clusterIssuer	any string	letsencrypt-production	The ClusterIssuer the Certificate references. tls=cert-manager
ingressClassName	any string	unset	Required when ingress=ingress; an Ingress with no class is claimed by no controller and applies cleanly anyway
traefikMiddlewareNamespace	any string	the deployment’s namespace	Where the HTTPS-redirect middleware lives. ingress=traefik
backupSchedule	five-field cron	17 3 * * *	The pg_dump CronJob. backups=pg-dump
pitrSchedule	six-field cron	0 47 2 * * *	The CNPG base backup. A five-field value is refused — see below
backupRetentionDays	integer	the tier’s — 7 at light, 30 at ha	Retention is durability, so it comes from the tier rather than the seam
backupBucket	any string	fountain-backups
backupSecretName	any string	fountain-backup-s3-credentials	The S3 credentials the backup path reads
backupS3Endpoint	a URL	floci’s in-cluster Service when storage=floci, otherwise unset	Unset means the AWS default endpoint — see below
flociImage	an image reference	floci/floci:1.5.34	Pinned. storage=floci
spritzerImage	an image reference	ghcr.io/intentius/spritzer:0.5.0	Pinned, because the emulator decides what a local conversation does. dataPlane=spritzer

Infisical

All seven apply only at secrets=infisical.

Parameter	Values	Default	Note
infisicalHostApi	a URL	http://infisical.infisical.svc.cluster.local:8080
infisicalProjectSlug	any string	empty	Nothing refuses an empty value
infisicalIdentityId	any string	empty	Nothing refuses an empty value
infisicalEnvSlug	any string	prod
infisicalSecretsPath	any string	/
infisicalServiceAccount	any string	fountain-infisical	The ServiceAccount the operator authenticates as
infisicalResyncSeconds	integer	60

emailDelivery=none is a decision with two edges

Under none the app self-verifies accounts at registration (fountain ADR 0011): a verification link that can never be delivered gates nothing, so the app stopped pretending otherwise. The other edge is that password-reset mail cannot be delivered either — a forgotten password is not recoverable in-app. For an instance whose accounts matter, configure real mail (emailDelivery=resend|smtp) or prefer OAuth sign-in.

databaseSsl is derived, and settable

Unset, it follows the postgres seam: false for bundled, which serves no TLS, and true for everything else. That default is right for a managed cloud database and wrong for a Postgres somebody else operates in your cluster, which is exactly the case postgres=reference exists for. Against one of those the app crashloops with (Postgrex.Error) ssl not available, so --param databaseSsl=false is how you say otherwise. Targets and tiers has the longer version.

pitrSchedule and backupSchedule are different dialects

CNPG cron is six fields, leading with seconds. A Kubernetes CronJob takes five. Both are accepted by the cluster and mean different times, so the two schedules are separate parameters and pitrSchedule is checked for its field count at build time. 47 2 * * * reads as 02:47 to every other cron and as second 47 of every minute 2 to CNPG — 24 base backups a day, with no error anywhere. The check and its message are on Seams.

backupS3Endpoint resolves from inside a pod

The only thing that reads it is the upload container, so the endpoint has to resolve from the cluster. At storage=floci it defaults to floci’s Service name, which does. A laptop-style http://localhost:4566 leaves the container talking to itself: inside a pod, localhost is the pod. Unset at storage=s3 means the AWS default endpoint, which is what a real bucket wants; point it at R2 or Garage to use one of those instead.

env and FOUNTAIN_ENV have to agree

env labels the resources. chant.config.ts reads FOUNTAIN_ENV from the process for ownership.env, because ownership is resolved when the config loads and build parameters do not exist yet at that point. So --param env=prod labels resources prod while the ownership marker still says dev unless FOUNTAIN_ENV says prod too. Set both or neither. INTENTIUS/chant#1396 tracks it. The justfile exports FOUNTAIN_ENV=local, so a local deploy is labelled, owned and bound under one name.

target and tier take the same treatment through FOUNTAIN_TARGET and FOUNTAIN_TIER, but those are ordinary parameter env mappings with nothing reading them behind the build’s back.

otelTraces is off, and says so

none is the default and the emitted value. fountain v0.4.0 exports traces only when an export target is configured, so this is an explicit statement of what would happen anyway — kept because “off” being visible in the pod spec is worth one line, and because the parameter is how an operator turns export on.

Setting otlp hands the decision back to OTEL_EXPORTER_OTLP_ENDPOINT and OTEL_EXPORTER_OTLP_HEADERS, which are yours to supply; nothing here models them.